REN and heart failure: ACEI, angiotensin‐converting enzyme inhibitor; ARB, angiotensin receptor blocker; ARNI, angiotensin receptor‐neprilysin inhibitor; βB, beta‐blocker; eGFR, estimated glomerular filtration rate; GDMT, guideline‐directed medical therapy; HF, heart failure; HFrEF, heart failure with reduced ejection fraction; MRA, mineralocorticoid receptor antagonist; RASi, renin‐angiotensin system inhibitor.